Arc discharge lamps, such as high and low pressure sodium, mercury and metal halide types, have a glass or ceramic hollow body containing therewithin an arc discharge generating and sustaining medium. Such mediums usually contain one or more metallic elements and one or more gases, as is well known in the art. Electrical current is supplied to the lamp via metal electrodes hermetically sealed in the lamp body. While this approach has worked for many years problems arise when the components of the lamp fill, or the operating temperature of the lamps, degrade the metal feedthroughs and shorten the expected lamp life. Additional problems can arise because the never quite perfect match of thermal expansion coefficients between the lamp body and the metal feedthroughs will eventually cause the lamp body or envelope to rupture.